Syringe assembly



Sept. 10, 1957 E. R. LAWSHE ET AL SYRINGE ASSEMBLY Filed Feb. 16, 1955 INVENTORS SYRHNGE ASSEMBLY Errol R. Lawshe, Ridgewood, and Albert E. Krug, Wyckoff, N. J., assignors to Becton, Dickinson and Conlpauy, Rutherford, N. I., a corporation of New ersey Application February 16, 1955, Serial No. 488,498

11 Claims. (Cl. 12S-216) This invention relates to a functionally and structurally improved syringe assembly of the hypodermic type.

It is an object of the invention to furnish a device of this character and in which the expulsion of medicament through the hypodermic needle will preferably occur as a consequence of a squeezing or compressing of the ampulse; the present invention assuring a proper positioning of that ampule within the holder or barrel of the assembly.

A further object is that of providing a structure of this nature in which assurance may be had that substantially all medicament within the ampule may be discharged therefrom, and in which, also, a user may operate the apparatus without fear of the plunger or piston failing to cooperate in a proper manner with the ampule to assure the desired discharge of medicament, in addition to the fact that there will be no danger of the parts jamming.

Still another object is that of providing a hypodermic syringe assembly in which the ampule may be readily associated with or removed from the holder or barrel and in which, moreover, the entire assembly will include relatively few parts, each individually simple and rugged in construction and capable of economical manufacture, to furnish a unitary mechanism functioning over long periods of time with freedom from all difficulties.

With these and other objects in mind, reference is had to the attached sheet of drawings illustrating practical embodiments of the invention, and in which:

Fig. 1 is a sectional side view of a complete assembly, showing the initial positioning of the parts;

Fig. 2 is a transverse sectional view taken along the line 2 2 in the direction of the arrows as indicated in Fig. 1;

Fig. 3 is a view similar to Fig. 1, but showing an alternative form of structure and also illustrating the positions of the elements at the final stages of the discharge stroke;

Fig. 4 is a transverse sectional view taken along the line 4-4 in the direction of the arrows as indicated in Fig. 3;

Fig. 5 is a perspective View of one form of ampule which may be employed; and

Fig. 6 is a fragmentary sectional side view, showing another form of ampule, with which a piston or plunger has cooperated in order to partially discharge the medicament.

With primary reference to Figs. 1 to 4 inclusive, the numeral 1li indicates a barrel or holder which is tubular adjacent its forward end and has projecting from its outer closed face a suitable mounting for a hypodermic needle. This mounting conveniently includes a tip 11 which cooperates with the bore of a needle hub in order to provide a 'liquid-tight seal between the surfaces thereof and to also afford a friction mounting for the needle. That needle may include a cannula 12 pointed at its opposite ends and suitably secured to a hub such as 13 mounted upon tip 11. The inner end of the needle has a length nied States Patent O ice such that it extends beyond the bore of the tip into the bore of the barrel 10.

Adjacent its opposite end, the holder may again present a tubular closed body 14, from the side faces of which linger rests or flanges 15 extend. A rod 16 of preferably non-circular cross-section may be centrally supported by the rear closed end 14 of the barrel by slidably extending through a similarly-shaped opening in that end. In this manner, rod 16 is prevented from rotating with respect to the barrel. While that rod has been shown as extending in line with the axis of the assembly, it is to be understood that it might be positioned, for example, upwardly of that axis. VSecured to the rear end of rod 16 is an actuator 17. A user by, for example, grasping the barrel between two fingers and with those fingers resting against the wings 15, may bring pressure upon rod 16 by engaging actuator 17 with his thumb. As a consequence of that pressure, the rod will be advanced.

Aixed to the inner end of rod 16 is a plunger or piston. This piston includes a body 18, conveniently formed of metal. The previously-described parts of the barrel assembly may be formed of similar material. In accordance with the present teachings, the forward face of the plunger is conveniently formed with a recess 19 and inclines downwardy and rearwardly, as indicated at 20. Thus, a camming surface is presented facing the bore of the holder. In lieu of the sled-type plunger 18, various other configurations may be resorted to so long as they present a forward face capable of exerting a squeezing' action on an ampule as the plunger is advanced through the bore. As shown in Fig. 1, the plunger, in completely retracted position, will preferably occupy a station where it may be wholly housed within the tubular rear end portion 14 of the barrel. If the plunger 18 embodies a configuration such that its forward end,'in effect, provides a sled surface, then, as especially shown in Figs. 3 and 4, the upper half of that plunger will present a diameter such that its side surface will slidably contact the adjacent bore face. Its lower part will present a reduced radius; the line of demarcation between these surfaces being defined by shoulders 22. Regardless of the specific configuration of the plunger, however, there should, in a manner similar to that just described, be furnished a space between the lower side face of the plunger and inner face of the barrel.

That barrel, between the tubular forward and rear end portions, has its side wall interrupted. Adjacent portion 14, the interruption is preferably in the form of a relatively deep notch 23, which, as shown, may extend into a plane below the axis of the apparatus. Beyond this, through, for example, an inclined surface, the notch becomes shallower and is defined by edge portions 24. Adjacent the forward closed end of the barrel, the notch is conveniently of even less depth and is defined by edges 25. In this manner, an ampule-enclosing structure. is furnished, which will assure a maximum support to the ampule, but at the same time will permit of the ready insertion thereof into the bore of the barrel and removal therefrom as hereinafter brought out.

That ample, as especially shown in Figs. l and 2, may include a tubular body, the upper half of which, in section, is relatively thin, as indicated at 26. The mating semi-circular section Z7 may be relatively thick. This thickness is preferably in an inward direct-ion or, in other words, the excess material extends into the bore of the ampule body. Accordingly, shoulders 28 will define the Zone of demarcation between these sections. These shoulders will lie generally in the Isame plane as the shoulder portions 22 of plunger 18. The forward front face of the ampule may have extending therefrom a circular lip or collar portion 29, which defines a socket in that face. The rear end of the ampule embraces a wall portion 31 extending downwardly and outwardly at an angle substantially equal` to the inclinationof'the. operative face 20 of the plunger. The rear and initially j for example, a rib 34 integral with the ampule body` and extending into a recess 35 in the barrel wall, and which recess may` be continued preferably in the form of a slot. The several parts of this ampule are formed of polyethylene embodying the characteristics of flexibility, surface smoothness and resistance to infiation distortion.

Similarly to the assembly just described, the ampule illustrated in Figs. 3 and 4 may be formed of a material having suitable characteristics, but in this instance the centering or guiding rib or its equivalent34, together with the slot 35 in the barrel, may be dispensed with. Also, the lip 29 may be eliminated, although, if desired, a recess 37 niay be provided in the inner surface of the forward end of the ampule. In common with the ampule of Figs. l and 2, the upper and lower walls of the element, when collapsed on each other, will present an aggregate thickness such that they may be accommodated below the shoulders 22 of the plunger or piston 18 and between that piston and the inner Asurface of the barrel.

This will also be true of the ampule 38, as shown in Fig'. 6. That ampule,` in lieu of having an integral forward wall, may have this end initially open. After filling with medicament, or previous thereto (the medicament is introduced through the rear end of the ampule) a stopper is inserted into the ampule bore. That stopper includes a plug 39 which may be formed with a `recess 40 and provided with a head 41 which overlies the forward `ampule edge and has a diameter substantially equal to that of the ampule. The inner face of plug 39 may also extend downwardly and rearwardly similar to surface 33 and correspond to the contour of the ejecting face of the plunger or piston.

Considering the operation of the assembly,lit will be understood that a needle `of the type shown is, for example, mounted on the forward end ofthe barrel, while the plunger is retracted to its fullest extent. An ampule is now introduced into the barrel bore in the manner shown in` dot-and-dash lines in Fig. 1. As will be apparent, no difficulty will be experienced in that introduction, in that the forward end of the ampule may readily enter through the notch portion 23 and be projected axially and parallel to the edges 24. Under continued projection, it will enter the partially confined space as defined by the wall portions terminating in edges 25. Finally, it will come to rest in a position such as has been shown in Fig. l. During this positioning of the parts, and espe cially if a centering structure as illustrated in the first two `figures is employed, the operator may carry foi'- ward with assurance that a proper relative disposition of the elements has occurred. This will be because the positioning flange or extension 34 will have entered the recess or slot 35. So disposed, all other parts will be` i rear surface 31 of the ampule. The parts will now move A guiding or positioning in unison under continued movement of the plunger and the inner end of the cannula 12 will enter recess 29 and penetrate the adjacent ampule wall so that its lumen will be in communication with the `medicament body within the ampule. As the plunger is further projected it is obvious that the forwardY end of the ampule will contact the inner face of the barrel end wall. Therefore, it will be arrested in its continued movement. Accordingly as plunger-projection is continued, the bore of the needle will have the air contained therein expelled by the entran-ce of the medicament into the inner end of the bore.

The outer end of the needle may now be plunged through the tissues at the site selected for the injection. Thereupon, by continuing to advance plunger 18, its forward face 20 will begin to cam against the outer surface of wall portion 26 and will collapse the latter to lie in intimate contact with the surfaceof wall portion 27 of the ampule. Therefore, the medicament within the arnpule will be squeezed or subjected to pressure such that it will be expelled through the needle 12. This action will continue throughout the entire working stroke of the piston or plunger. Thelatter will finally reach a station adjacent inner surface 33 and will force the inner surface of walll26 into contact with that face. As a consequence, all medicament within the ampule will be `expelled through the bore of the needle.

l'ii other words, there will be no pocketing of a residue of the medicament. When the parts finally reach the position shown in Fig. 3, and after withdrawal of the needle from the tissues, the plunger may be retracted. At that time the `ampule may be freely dislodged from the barrel bore by simply grasping the wing or end zone surfaces of the irear end 32 and lifting and withdrawing the ampule through notch portion 23. To facilitate this dislodgment, pressure may be brought against the exposed edge surface of rib 34, which, as shown, may have ia thickness slightly greater than the wall thickness through whichopening 35 is formed. Of course, if the parts are in the position shown in Fig. 1 and it is desired, for

some reason, to dislodge the ampule before beginning` expulsion of medicament. then this rib portion may be similarly employed to effect this result.

Precisely the same effect and end result will follow in the structure shown in Fig. 6. In this case, as the sled face 20 of the plunger reaches a position where it is substantially fully projected, it will force the inner surface of wall 26 into contact with the inner face 42 of plug 39, thus assuring an expulsion of substantially all of the medicament within the ampule. Of course, if a plunger having an operative face different from that of a sled, or a plunger having a rolling contact, is employed, this inner surface of the stopper plug may be suitably modified in contour. This is also true of surfaces 33 in the previouslydescribed ampules. In all of these `arnpules, by having a preferably thickened lower section 27, the unit is rigidified whereas the relatively thin wall 26 is quite flexible and susceptible` of collapse against the inner surface of the lower portion of the ampule. `'This relative thickening, of course, may be modified or eliminated without sacrificing the desired functional results by treating the plastic of the ampule body so that it will have a lower zone which is relatively rigid while its upper half is quite flexible.I

As will be understood, the several recesses provided in the ampule end serve to permit of a centering of the inner needle end with ythe area to be punctured. ln the case of the recesses formed in the operative face of the piston, a space is furnished for the accommodation of the inner needle end. Accordingly, damaging contact between the parts will be prevented.

Thus, among others, the several objects of the invention as specifically aforenoted are achieved. Obviously, nu merous changes in construction and rearrangements of the parts might be resorted to without departing from the spirit of the invention as dened by the claims.

We claim:

1. A syringe assembly including in combination a holder comprising a tubular body element, a plunger projectable through the bore of said body towards one end of the same and movably supported adjacent the opposite end of said holder, an ampule element within said bore, both said elements having side faces and a projection extending from the side face of and forming a part of one of said elements and keying within a recess formed in the second of the same to assure an initial predetermined disposi# tion of said elements with respect to each other.

2. A syringe assembly including in combination a holder comprising a tubular body element, a plunger projectable through the bore of said body towards one end of the same and movably supported adjacent the opposite end of said holder, an ampule element within said bore, both said elements having side faces and guiding means in such side faces and cooperating to assure a proper disposition of said ampule within said holder.

3. A syringe assembly including in combination a holder comprising a tubular body element, a plunger projectable through the bore of said body towards one end of the same and movably supported adjacent the opposite end of said holder, an ampule element within said bore, a portion forming a part of said ampule and projecting outwardly from one side face thereof, said holder being formed with an opening to receive said portion and the surfaces of the latter and said opening cooperating to provide a centering structure to assure an initial predetermined position of said ampule within said holder.

4. A syringe assembly including in combination a holder comprising a tubular body element, a plunger projectable through the bore of said body towards one end of the same and movably supported adjacent the opposite end of said holder, an ampule element disposed within said bore, a portion forming a part of said ampule and projecting outwardly from one side face thereof, said portion having a height greater than the thickness of the wall through which said opening is formed whereby the edge of said portion will extend beyond the outer face of said body element and be engageable to expel said ampule from the bore of said holder.

5. A syringe assembly including in combination a holder comprising a tubular body element, a plunger projectable through the bore of said body towards one end of the same and movably supported adjacent the opposite end of said holder, to slidably engage a substantial zone of the bore surface of said body element, an ampule element within said bore and substantially completely lling the same, said ampule having longitudinally extending collapsible and relatively rigid wall zones and said plunger being recessed throughout a part of its circumference to clear the bore surface of said body element and provide a space between such surface and a zone of its circumferential face to accommodate the superposed layers of the ampule when the latter is in collapsed condition, an actuator secured to said plunger at a point beyond said opposite end of the holder and a needle in communication with said ampule and extending from that end of the tubular body element towards which said plunger is projectable.

6. A syringe assembly including in combination a holder comprising a tubular body element, a needle having a bore and mounted to extend beyond one end of said element, a plunger projectable through the bore of said body towards said needle and movably supported adjacent the opposite end of said holder, an ampule element disposable within said bore, said ampule in cross-section presenting an arcuate and relatively thin collapsible wall portion and a relatively thick, arcuate and rigid mating wall portion, said plunger and the bore surface of said tubular body element providing between them space to accommodate the superposed wall sections of said ampule when the relatively thin wall portion of the latter is collapsed into engagement with the adjacent surface of the relatively rigid wall portion thereof, means for assuring such collapse as said plunger is projected and an actuating portion mounted by said plunger to the rear of the opposite end of said holder.

7. ln a syringe assembly in combination a holder comprising a tubular body, a plunger projectable through the bore of said body towards one end of the same and movably supported adjacent the opposite end of the holder, said holder being adapted to receive within its bore an ampule and the bore surface of said holder providing means to cooperate with the side portion of such an ampule to prevent a rotation of the latter within said holder.

8. In a syringe assembly, an ampule comprising a tubular body, said ampule in cross-section including an arcuate portion of substantial flexibility and a mating arcuate portion of relatively high rigidity and a positioning pro jection extending outwardly from the outer side face of the latter portion.

9. In a syringe assembly, a tubular collapsible ampule having an outer surface to be slidably engaged by a plunger for the purpose of collapsing the same, a forward end part for said ampule closing the bore of the same and the inner face of said forward end part being inclined at an angle intermediate the axis and a plane normal to the axis of said ampule.

10. In a syringe assembly in combination a holder cornprising a tubular body having a bottom surface in its bore, a plunger projectable through the bore of said body towards one end of the same and movably supported adjacent the opposite end of said holder, said body being adapted to receive an ampule within its bore and the bottom bore surface being formed with a recess to accommodate a projecting portion of said ampule to prevent relative rotation of the latter within said bore.

1l. In a syringe assembly, an ampule, said ampule comprising a body having an encircling side wall to contain medicament and at least a part of said side wall being collapsible to expel that medicament from the bore of the ampule, said ampule being disposable within a t-ubular syringe barrel, and positioning means forming a part of said ampule and extending outwardly from the face of said side wall to be engaged by a barrel part to prevent rotation of said ampule when the latter is positioned within the barrel bore.

References Cited in the file of this patent UNITED STATES PATENTS 401,950 Haussmann Apr. 23, 1889 818,000 Stevenson Apr. 17, 1906 1,799,678 Devlin Apr. 7, 1931 1,844,215 Edwards Feb. 9, 1932 2,399,796 Freedman May 7, 1946 2,535,671 Cutler Dec. 26, 1950 

